In addition to Reynolds, Watanabe — who will slip into a role specifically created for the movie — joins Justice Smith, who will be seen in the upcoming Jurassic World: Fallen Kingdom, and Big Little Lies actress Kathryn Newton in the movie based on the gaming franchise.

Rob Letterman (Goosebumps) is directing the project, which is due to start shooting this month in London.

The concept of Pokemon sees players acting as trainers who collect cute but powerful monsters called Pokemon in order to compete in battle tournaments.

Pikachu is a species of Pokemon, while Detective Pikachu the character is a peculiar sort from the Pikachu set, a self-styled investigator who is good at finding things.

The story is set into motion when Smith's character's father is kidnapped, forcing the teen to team up with Pikachu in order to find him.

Watanabe will play a character named Detective Yoshida.

Nicole Perlman and Alex Hirsch wrote the script with Eric Pearson and Tom McCarthy having completed production polishes.